As you can see.... This is very old research....
Recentry, I have not worked on this reseach, however, I still have intersts in
this field.....
I'm still interested in `Tractable Reasoning.'
References:
Ishizuka M. and Abe A.: Fast Hypothetical Reasoning
Using Analogy on Inference-path Networks, Proc. of TAI, pp. 232--239 (1993)